Corundum is a crystalline form of aluminum oxide and is found in various different colors, most of which are generally referred to as sapphire. Sapphire is a hard and strong material with a hardness of 9.0 on the Mohs scale, and, as such, is capable of scratching nearly all other minerals. Because of its hardness and strength, sapphire may be an attractive alternative to other translucent materials like glass or polycarbonate. Sapphire may also be produced in thin sheets and polished to achieve exceptional optical performance.
However, in some cases, it may be difficult to process thin, highly polished sheets of sapphire material using traditional techniques. For example, performing a fusion laser cut on a polished sapphire sheet may result in a spatter of molten sapphire deposited on the polished surface. Once cooled and hardened, the spatter may adhere to the polished surface and require further processing to remove. Additionally, in some cases it may be difficult to initiate a laser cut in a sapphire sheet having a highly polished face that does not readily absorb the laser energy.